Cancers of the digestive system are very common and often fatal. For example, colon carcinoma is the second leading cause of cancer death'. Although there is increasing evidence that a rare population of undifferentiated cells is responsible for tumour formation and maintenance2-4, such hypothesis has not been explored for colorectal or pancreatic cancers.
Surprisingly, it has now been established that the malignancy of colon cancers is driven by a very small percentage of the cells making up the cancer, and that these cells are characterised by the presence of the CD133 marker. Cells carrying the CD133 marker are referred to herein as CD133+ cells.